In recent years, with the proliferation of smartphones, smart devices, and the like, communication traffic is sharply increasing, so that network congestion easily occurs. Accordingly, several techniques are proposed for easing network congestion.
For example, PTL 1 discloses a technique in which a plurality of types of radio system are switched depending on the status of network congestion. A terminal, if it is capable of operating in both cellular communication and Wireless LAN (Local Area Network) as radio systems, can perform congestion determination and select an optimum radio system. For example, traffic on the cellular communication is switched to a wireless LAN network, whereby it is possible to ease congestion in the cellular network.